Articulated sculling oar

ABSTRACT

Disclosed is a collapsible sculling oar designed for universal pivotal attachment to a boat, especially small watercraft, to impart motion thereto in a manner generally known as &#39;&#39;&#39;&#39;sculling.&#39;&#39;&#39;&#39; The oar includes a shaft portion extending generally horizontally over the boat, an adjustable handle removably mounted at one end of the shaft, and at least one adjustable blade-supporting arm removably mounted at the other end of the shaft and depending substantially vertically therefrom into the water, in spaced relation from the boat. The blade is arranged to move back and forth on the supporting arm through a predetermined arc of movement, a depressible protrusion being arranged on the arm to limit movement of the blades relative thereto and to permit displacement of the blade from one position to another for opposed sculling movement. A lever-operated locking mechanism is provided to halt movement of the blade on the arm and to lock the former into a predetermined position such as to constitute a ruddering effect of the blade. Dual blade embodiments are likewise disclosed.

United States Patent [19] Hopkins 1 ARTICULATED SCULLING OAR [76]Inventor: Walter M. Hopkins, 1306 W.

Glenoaks Blvd., Glendale, Calif.

[22] Filed: Nov. 14, 1972 [21] Appl. No.2 306,489

115/29, 21, 22.1, 22.2, 22.3, 26.3, 25, 24.2; 416/69, 74, 70; 74/522,523, 525, 543, 548, 551.3, 551.4, 480 B; 114/162; 287/58 CT [56]References Cited UNITED STATES PATENTS 453,338 6/1891 Frostad ..-ll4/162557,318 3/1896 Tenney 416/74 610,469 9/1898 Blashfield 74/551.41,925,912 9/1933 Strout 115/28 2,097,931 11/1937 Martin 115/30 2,365,41512/1944 Kruse 115/28 2,747,425 5/1956 Chlau 114/162 2,809,604 4/1955Meredith 115/28 R 2,826,164 3/1958 Hutchinson 115/29 2,926,544 3/1960Carmichael 74/480 B 3,086,492 4/1963 Holley l15/24.1 3,214,187 10/1965Fuerst.. 287/58 CT 3,505,901 4/1970 Stone 74/55l.4

[4 Sept. 10, 1974 Primary Examiner-Duane A. Reger AssistantExaminer-Galen L. Barefoot Attorney, Agent, or Firm-John E. Wagner {57]ABSTRACT Disclosed is a collapsible sculling oar designed for universalpivotal attachment to a boat, especially small watercraft, to impartmotion thereto in a manner generally known as sculling. The oar includesa shaft portion extending generally horizontally over the boat, anadjustable handle removably mounted at one end of the shaft, and atleast one adjustable bladesupporting arm removably mounted at the otherend of the shaft and depending substantially vertically therefrom intothe water, in spaced relation from the boat. The blade is arranged tomove back and forth on the supporting arm through a predetermined arc ofmovement, a depressible protrusion being arranged on the arm to limitmovement of the blades relative thereto and to permit displacement ofthe blade from one position to another for opposed sculling movement. Alever-operated locking mechanism is provided to halt movement of theblade on the arm and to lock the former into a predetermined positionsuch as to constitute a ruddering effect of the blade.

Dual blade embodiments are likewise disclosed.

9 Claims, 8 Drawing Figures mcmauswww 3.8%84343 SHEH 30$ 3 1 ARTICULATEDSCULLING OAR BACKGROUND OF THE INVENTION The present invention relatesto boat propelling means, and more particularly to a new, improved andcollapsible sculling oar especially adapted for use with smallwatercraft and arranged to operate by the backand-forth movement of ablade or a plurality of blades, in a manner generally known as sculling.

Already known in the art are impuller devices mounted for universalpivotal movement to the stern, bow, or other support of the boat, andbeing generally of the character as described above. Known, for example,are propulsion devices which employ a rod terminating into a handle atone end thereof while the other end is angular and depends into thewater, adjacent the boat, to pivotally support at least one blade orvane. The latter are arranged to be oscillated in conventional manner,generally horizontally in the line of movement of the boat, this beingeffected by oscillating the shaft back and forth in a horizontal plane.Usually incorporated are limited members which serve to limit theoscillating or back and forth movement of the blade or blades relativeto the supporting arm, usually through an arc of 120", or a variationthereof. Additionally, and as a matter of choice, the blade or bladesmay be reversed as to propulsion direction. For example, one impellerinstallation is known and arranged suchv that when the vane or blade isoscillated, it will push the water sidewise or rearwardly to provide aforward drive for the vessel, and, by snapping the handle to an axiallyopposite direction, the blade or vane, likewise, axially turns throughapproximately 180 and provides a reverse drive, i.e., a backward drive.Obviously, complicated provisions have to be made to enable reversal .ofthe blade in response to reversal of the'handle such as to accomplishthe aforementioned propulsion action of the impeller drive from forwardto backward driving action. Positioning of the impeller device on or tothe boat is a matter of choice, for example, the impeller may bepositioned at the stern, at the bow or somewhere mid-ships between thestem or bow. Also, the impeller device may be arranged such as to permitrelocation thereof from one driving position to another.

However, none of the conventional devices shows an arrangement whichenables the blade or vane to be easily manually converted from a drivingmember to a ruddering device for steering the boat.

Due to the rather complicated construction of conventional impellerdevices, easy disengagement and/or collapsibility of the various partsrelative to one another, is practically impossible. For example, thehandle, usually is not adjustable relative to the rod while, likewise,the rod is not adjustable with respect to the blade-supporting arm. Asregards the blades or vanes, the latter, usually, are mounted in such acomplex manner that it becomes a time-consumming affair to replace oradjust them. Adjustability of the blade or blades and shafts isimportant, particularly since boats are not uniformly designed. Onoccasion, the impeller device may have to operate under a conditionwhere the boat hardly permits oscillation of the handle and, thus,adjustability of the handle or shaft would be necessary.

In case of breakage of any given part of such impeller devices, theentire device will have to be forcibly dismantled so as to enablereplacement of the broken part or parts. A further obvious disadvantageis that such non-collapsible devices are not suitable or adapted foreasy storage or carrying purposes.

BRIEF STATEMENT OF THE INVENTION In view of the foregoing representativeprior art, there remains a need for an improved easily collapsiblesculling oar designed for universal pivotal attachment to the stern,bow, or other supporting structure of a boat, especially smallwatercraft.

A major object of the invention, therefore, is to provide such an oarwhich incorporates the advantages of compactness and of minimum weight,which may be readily manufactured at small expense and may be operatedeither by hand or foot at minimum effort, and which is adapted for useon boats or crafts of many kinds.

Another object is to provide such a sculling oar which is adapted foreasy conversion from a motion imparting member to a hand operated rudderfor steering the boat.

Still another object of the invention is to provide a sculling oar whichincorporates an adjustable handle which provides the operator maximumcomfort from a variety of positions within the craft.

A still further object of the invention is to provide a sculling oarwhich provides the feature of easy replacement or detachment of thesculling blade from the support arm of the oar.

According to the invention such sculling oar comprises a shaft which isadopted to extend generally horizontally over a boat transom andincludes an angular blade support arm extending generally verticallyinto the water in spaced relation from the boat. A handle, within thecraft, is arranged for oscillation of the shaft and includes positioningmembers for positioning the handle in a plurality of positions relativeto the shaft. A mounting arrangement which may be of any conventionaldesign, serves to attach the shaft to the boat for universal pivotalmovement relative thereto. Pivotally mounted to the angular blade arm isat least one generally planar blade which is movable betweenpredetermined limits-detined by an integral, internal slot in the bladeand a protruding depressible pin on the supporting arm which travelsbetween the extremeties of the slot to limit the lateral deflection ofthe blade relative to the arm. Depression of the pin enables reversal ofthe blade through from a first position to a position axially oppositethe first position. Also, depression of the pin permits removal of theblade from the supporting arm, simply by sliding the blade downwardlyfrom the arm. In similar fashion as the handle, also the supporting armmay be positioned at different angles relative to the shaft. Finally alever-actuated latch mechanism is provided to manually selectively haltoscillating or sculling movement of the blade and lock the latterin afixed position relative to the supporting arm such as ,to constitute aruddering effect of the blade.

Dual blade embodiments also incorporate the advantages of the abovedescribed invention.

BRIEF DESCRIPTION OF THE DRAWING Other features and advantages of theinvention will appear from the following description taken in connectionwith the drawing, wherein:

FIG. 1 is a perspective view of a known impeller device associated witha typical watercraft;

FIG. 2 is a side elevational view of a sculling oar embodying theprinciples of the present invention, the oar being associated with asmall boat;

FIG. 3 is an exploded side view of the sculling oar of FIG. 2;

FIG. 4 is a diagrammatic illustration of the blade release and lockingarrangement incorporated in the construction of FIG. 2, showing, insolid lines, the blade in locked or ruddering position and, in dottedlines, the blade in released or sculling position;

FIG. 5 is an end elevational view of the sculling oar of FIG. 3,associated with a multi-hull watercraft;

FIG. 6 is a front elevational view of a further embodiment of a scullingoar embodying the invention, illustrating a dual blade constructionincorporating the blade release and locking arrangement of FIG. 4;

. FIG. 7 is a top plan view of the sculling oar of FIG. 6, illustratingthe arrangement as mounted to the transom or hull section of a boat, theposition shown being at a point during the travel of the blades insculling movement; and I FIG. 8 is a top plan view of the sculling oarof FIG. 6 mounted to the bow of a boat in position for straightaheadmovement, the blades being reversed in this position.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Now referring to the drawingsin which like reference numerals index like parts, and with attentioninitially drawn to FIG. 1 there is shown a typical watercraft or smallboat 10 of conventional design. Mounted to the transom 12 of the boat 10for universal pivotal movement in a typical oar lock 14, is an impellerof the prior art generally indicated at 16. Impellers of this type arearranged for imparting motion to the boat 10*, in a manner similar tothat which is known as sculling, comprises a shaft 18, a handle ortiller portion and a downwardly depending blade supporting arm 22. Asshown, the arm 22 extends substantially vertically into the water,spaced from the boat 10. Pivotally and substantially vertically mountedon supporting arm 22, for swinging movement in a substantiallyhorizontal plane, is a planar impeller blade 24. Conventionally, as thehandle 20 is moved from the central axis Z in direction D, the blade ismoved in direction E.

Pivotal mounting of the blade 24 on the supporting arm 22 may beeffected in a number of ways, e.g., by

means of a blade retaining collars or sleeves, not shown, fixed atopposite ends of the blade to portion 22, or by other means. A pair ofdivergent arms 26 and 28 may be provided and act as stops to limit thearc of movement of the blade relative to supporting arm 22.

In FIGS. 2 and 4, a preferred form of sculling oar according to theinvention, is disclosed and indicated generally at 30. It is shown asassociated with a typical watercraft 32, similar to that of boat 10 ofFIG. 1. The sculling oar 30 comprises a shaft 34 which extends generallyhorizontally over the transom 36 of the boat 32 and is mounted theretoby means of a conventional oar lock 38'for universal pivotal movementrelative tothe boat.

As shown, the shaft 34, at its inner end 40 is connected to a normallyslightly upwardly curved handle 42 by means of a connecting portion 44of the handle i '42 seen in FIG. 3. The inner end 40 of the shaft 34 isof a diameter slightly less than that of the handle connecting portion44 and is slidably received therein. The handle 42 isposition-adjustable relative to the shaft 34 by means of a positioningarrangement comprising a depressible pin member 46 engaging a pluralityof holes 48 in handle 42 each adapted to receive the pin 46. In apreferred form, four holes 48 are provided at this end and with each ofthe holes spaced apart through about 90 relative to each other. As willbe appreciated. this combination with the pin and holes permits thehandle to be positioned at four different angles relative to the shaft.

The opposite end of the shaft 34 is connected to a shaft extension 50including an angled arm portion 52 extending at approximately relativeto the sh ft anddepending generally vertically into the water, FIG. 2.This arm portion 52 constitutes a supporting arm pivotally mounting atleast one blade 54. The blade 54, as clearly shown in FIG. 4, is seen tocomprise a generally planar blade section 56, a longitudinally extendingblade support sleeve 58 pivotal about the arm '52 and an integralsheath-shaped portion 60 mounting the actual blade section 56 to theblade sleeve 58. The blade, preferably, is made of a plastic materialand, preferably, is cemented in the slot defined between the two layersof the sheathshaped portion 60.

FOrmed into the blade sleeve 58, adjacent one end thereof, are a pair ofradially opposed slots 68, best seen in FIG. 4 extending arcuately andtransversely relative to the longitudinal axis of the sleeve 58.Arranged for travel within the slots and between the extremeties thereofis a protruding pin 72 depressibly mounted on the arm'52. The pin 72serves a triple purpose:

I. Upon depressing the pin the blade 54 is free to be slidably removedfrom the arm 52, for example, for repair or replacement;

II. And again upon depressing the pin 72, the blade may be rotatedthrough 180 from a first position to an axially opposite positionrelative to the arm 52, which, for example, is necessary when the boatis to be driven in reverse direction, or, is necessary for moving theboat in straight-ahead direction but with the sculling oar mounted atthe bow of the boat. It will be understood that in rotating the bladefrom one position to the other, the pin is snapped through 100 from oneslot, e.g., slot 68 to the other slot, in this case slot '70; and

III. The feature of the pin traveling between the extremities of theholes limits the oscillating movement of the blade 54 relative to thearm 52.

Similarly, and as has been described above, the adjustment of the handle42 relative to the shaft 34 the extension 50 and supporting arm 52 areinterconnected so that the extension 50 can be positioned in a pluralityof positions relative to the shaft 34 by a depressible pin making holes81. The holes 81 are spaced apart through approximately relative to eachother and, upon depressing the pin 80 and snapping into one of the holes81, the extension 50 is locked against movement relative to the shaft34. In this manner, the extension 50 and arm 52 aregiven a desiredangularity relative to the shaft 34. This may be of great importance,for example, where the boat encounters shallow waters and blademovement, about a vertical axis, is impossible. Under such conditionsall that is required is to rotate the handle 42 and extension 50 90relative to the shaft 34 in which case the blade 54 will oscillate abouta horizontal axis in response to up and down movement of the handle.

In a preferred embodiment of the invention, and as shown in FIG. 3, thearm 52 extends at approximately 110 relative to the extension 50 whereasthe latter extends through about 160 relative to the shaft 34. Again,this is of importance in that if the angle between the extension 50 andthe shaft 34 were more acute, the operation of the sculling oar would bedifficult in rather shallow waters.

FIGS. 2, 3 and 4 illustrate a sculling oar incorporating a manuallyoperable locking arrangement embodying the invention. This arrangementserves to place the blade 54 in a fixed or stationary position relativeto the supporting arm 52. The locking arrangement is seen to comprise aconventional lever-operated over-center cam lock, generally indexed byreference numeral 82 and positioned on the shaft 34 within easy reach ofthe operator oscillating the handle 42. The cam lock 82, by means of acable 84, is connected to an axially movable spring-biased locking pin86 positioned on the arm 52 and adapted, upon placing the lever 88 ofthe cam lock 82 in pin locking position, position Y, FIG. 4, to placethe locking pin 86 in a locking location in the slot 62 of theblade-connection 60, FIG. 3. In this condition, the blade 54 isprevented from lateral movement relative to the supporting arm 52 bymeans of the pin 86. In order to release the pin, and restoreoscillation of the blade 54 relative to the arm 52, it is only necessaryto move the lever 88 from its position Y to its position X, FIG. 4, inwhich case the pin 86 is retracted from its locking location by means ofcable 84.

As can be seen from FIG. 4, a spring member 92 is provided to bias thelocking pin 86 into its locking position upon placing the lever in itsposition Y. A housing 94 is provided to retain the spring 92 and to keepsame in loaded condition for easy switching from position X to Y. Thehousing as shown, is affixed to the supporting arm 52, in this example,by means of rivets. At its outer ends, the cable 84 is provided withclasps or eyes connecting the locking pin 86 and the lever 88.

FIG. 5 shows the sculling oar of the invention incorporated in amulti-hull boat, merely for reasons as to show the applicability of theinvention to a variety of boats, which may be single-hulled ormulti-hulled. Operation of the sculling oar, likewise, is similar tothat described with respect to FIG. 2. In the present illustration,however, the sculling oar of the invention operates between therespective hulls of the boat shown. In this case the oar mayadvantageously be secured far forward and the handle intermediate theoar lock and the blade.

In the construction illustrated in FIG. 6 and FIG. 7, the shaft 34 isprovided with two blade supporting arms 52 extend generally outward in aV shape with the arms suitably secured to each other. In FIG. 6, forexample, the arms 52 are welded together and form a joint section 102with the arm portions at this joint extending parallel to each other. InFIG. 7 the arms are connected together by means of a triangular bracket53 in any suitable manner. In FIG. 7 the arms 52 are positionadjustablewith respect to each other to vary the angle 6. Similar to FIGS. 2-4 thehandle 42 is positionadjustable with respect to the shaft 34 asdescribed hereinbefore. Optionally incorporated in the embodiment ofFIGS. 6 and 7 is the cam-locking arrangement 83, described with regardto FIG. 2-4. Both arrangements, FIGS. 6 and 7, are shown to be mountedto the transom of a boat by means of any suitable oar lock whichprovides universal pivotal movement of the sculling oar on the boat.

As regards FIG. 7, the illustration shows the optimum travel limits foreach blade to be 135. Examination will show, however, that the mostefficient angle will depend upon the length of the shaft 34 and thelength of the supporting member 52 which hold the blades 54. The angularrelationship of the blades 54 to the axis (and hence the transom, lineof movement, etc.) will vary as a product of these dimensions of length.The most efficient angle involves a total of -l30 of travel with theuseful angle rangeof 90 to In operation as handle C is moved from L toR, blades A and B are moved from R to L. As shown by the solid arrows,maximum work force of blade B is exerted at midpoint of travel. Whileblade B is exerting maximum resistance to water at this position, bladeA is nearly parallel to the arc of movement and exerts little pressureagainst water. As assembly progresses from R to L, blade B continues topresent a broad decreasingly effective force. As limited, desired travelis reached and handle C is moved from R to L, blades A and B arearrested in their movement and are free to rotate to stop positionsshown by dotted lines. Angles as shown in FIG. 7 allow water resistanceto effectively move the blades to these stop positions withoutresistance. At this end, blade A now assumes the position of effectiveresistance to water while blade B presents little resistance on thisreturn stroke. The net effect of this movement exerts a propulsive forcewhich is transmitted to the boat structure through the pivot assembly.

FIG. 8 illustrates that the oar of FIG. 6 and 7 may similarly be bowmounted. The reversible nature of the blade mounting as illustrated inFIGS. 2-4 makes this possible and practical.

Above, I have described a new light weight oscillating sculling oarwhich is adjustable in several modes and lockable for use as a rudder.The blade, locking mechanism and stop arrangements are all simple yeteffective and cooperate in a novel fashion.

The above described embodiments of this invention are merely descriptiveof its principles and are not to be considered limiting. The scope ofthis invention instead shall be determined from the scope of thefollowing claims, including their equivalents.

What is claimed is:

l. Impeller for small boats, comprising:

a shaft adapted to extend generally horizontally over a boat transom andincluding an angular projection depending substantially vertically intothe water and spaced from the boat;

a handle for oscillating said shaft and said angular projection thereof;

said shaft and handle including adjustable means for permitting saidhandle to be snapped from one offset position to a plurality of suchpositions with respect to said shaft;

means adapted to mount said shaft to the boat for universal pivotalmovement;

at least one generally planar blade pivotally attached to said angularprojection for oscillating movement relative to said angular projectionin response to oscillation of said handle;

limit means on said angular-projection and said blade for limiting theoscillating movement of said blade between divergent limits, said limitmeans permitting said blade to snap from one oscillating position toanother relative to said angular projection; and

manually operable control means on said shaft and said projectionthereof for selectively halting oscillating movement of said bladeandfor locking the latter into a predetermined position intermediate saiddivergent limits whereby to constitute a ruddering effect of saidblade;

wherein said blade constitutes a unitary member including a tubularmounting portion defining a slot extending transversely relative to thelongitudinal axis of said mounting portion, and wherein said limit meanscomprises a stop member extending outward from said angular projectioninto said slot and movable therein between opposite ends thereof tolimit the rotation of said blade.

2. Impeller for small boats, comprising:

a shaft adapted to extend generally horizontally over a boat transom andincluding an angular projection depending substantially vertically intothe water spaced from the boat;

a handle for oscillating said shaft and said angular projection thereof;

said shaft and handle including adjustable means for permitting saidhandle to be snapped from one offset position to a plurality of suchpositions with respect to said shaft;

means adapted to mount said shaft to the boat for universal pivotalmovement;

at least one generally planar blade pivotally attached to said angularprojection for oscillating movement relative to said angular projectionin response to oscillation of said handle; I

limit means on said angular projection and said blade for limiting theoscillating movement of said blade between divergent limits, said limitmeans permitting said blade to snap from one oscillating position toanother relative to said angular projection; and

manually operable control means on said shaft and said projectionthereof for selectively halting oscillating movement of said blade andfor locking the latter into a predetermined position intermediate saiddivergent limits whereby to constitute a ruddering effect of said blade;

wherein said blade includes a tubular mounting portion and defines apair of v radially opposite slots extending transversely relative to themain axis of said mounting portion; and

wherein said limit means comprises a depressible stop member extendingfrom said angular projection, said blade being arranged to be rotatedrelative to said mounting portion upon depressing said stop member suchas to permit displacement of said blade through 180 from one directionto an axially opposite direction in which position said pin extends intothe other one of said slots.

3. Impeller for small boats comprising:

a shaft adaptedto extend generally horizontally over a boat transom andincluding an angular projection depending substantially vertically intothe water spaced from the boat; a

a handle for oscillatingsaid shaft and said angular projection thereof;

said shaft and handle including adjustable means for permitting saidhandle to be snapped from one offset position to a plurality of suchpositions with respect to said shaft;

means adapted to mount said shaft to the boat for universal pivotalmovement;

at least one generally planar blade pivotally attached to said angularprojection for oscillating movement relative to said angular projectionin response to oscillation of said handle;

limit means on said angular projection and said blade" for limiting theoscillating movement of said blade between divergent limits, said limitmeans permitting said blade to snap from one oscillating position toanother relative to said angular projection; and

manually operable control means on said shaft and said projectionthereof for selectively halting oscillating movement of said blade andfor locking the latter into a predetermined position intermediate saiddivergent limits whereby to constitute a ruddering effect of said blade;

wherein said shaft includes a tubular extension including said verticalarm portion depending therefrom; and

wherein said blade comprises a unitary member including an elongatedsleeve rotatable about said vertical portion and defining a pair ofradially opposite slots therein extending transversely relative to axisof said sleeve; and

wherein said vertical arm portion comprises a normally protruding pinmember, depressible relative to said vertical arm portion and adapted tobe selectively journaled betweenthe ends of said slots such as to limitoscillating movement of said blade relative to said arm portion.

4. Impeller for small boats comprising:

a shaft adapted to extend generally horizontally over a boat transom andincluding an angular projection depending substantially vertically intothe water spaced from the boat;

a handle for oscillating said shaft and said angular projection thereof;

said shaft and handle including adjustable means for permitting saidhandle to be snapped from one offset position to a plurality of suchpositions with respect to said shaft;

means adapted to mount said sahft to the boat for universal pivotalmovement;

at least one generally planar blade pivotally attached to said angularprojection for oscillating movement relative to said angular projectionin response to oscillation of said handle;

limit means on said angular projection and said blade for limiting theoscillating movement of said blade between divergent limits, said limitmeanspermitting said blade to snap from one oscillating position toanother relative to said angular projection; and

manually operable control means on said shaft and said projectionthereof for selectively halting oscillating movement of said blade andfor locking the latter into a predetermined position intermediate saiddivergent limits whereby to constitute a ruddering effect of said blade;

wherein said shaft includes a tubular extension including a vertical armportion depending therefrom; and

wherein said blade includes an integral elongated sleeve memberrotatable with predetermined limits about said arm portion and defininga pair of radially opposed arcuately shaped slots therein extendingtransversely relative to the axis of elongation of said sleeve portion;and

wherein said vertical arm comprises a normally-protruding pin member,manually depressible relative to said vertical arm, said blade beingarranged to be rotated relative to said vertical arm upon depressingsaid pin member such as to permit displacement of said blade through 180from one direction to an axially opposite direction in which positionsaid pin member extends into the other one of said slots.

5. A sculling oar comprising:

a shaft,

means for mounting said shaft to overhang the edge of a watercraft to bepropelled,

an extension for said shaft including an angular depending portion and atubular portion extending substantially vertically,

a blade secured about said tubular portion for rotatable movement abouta substantially vertical axis,

first pin means within said tubular portion engaging stops integral withsaid blade for limiting angular movement of said blade,

second pin means extendable in and out of said blade and tubularportions of said extension for selectively locking and unlocking saidblade for oscillatory movement about said tubular portion of saidextension, and

means secured to said shaft for controlling said second pin means.

6. The combination in accordance with claim wherein v a pair ofextensions are connected to said shaft and each having a respectiveblade secured thereto,

said pair of extensions having lateral angular displacement from eachother to provide a pair of laterally displaced blades controlled by saidshaft.

7. The combination in accordance with claim 5 wherein said extensionsare angularly adjustable.

8. Impeller for small boats comprising:

a shaft adapted to extend generally horizontally over a boat transom andincluding an angular projection depending substantially vertically intothe water spaced from the boat;

a handle for oscillating said shaft and said angular projection thereof,said shaft and handle including adjustable means for permitting saidhandle to be snapped from one offset position to a plurality of suchpositions with respect to said shaft;

means adapted to mount said shaft to the boat for universal pivotalmovement;

at least one generally planar blade pivotally attached 6 limit means onsaid angular projection and said blade for limiting the oscillatingmovement of said blade between divergent limits, said limit meanspermitting said blade to snap from one oscillating position to anotherrelative to said angular projection; and

manually operable control means on said shaft and said projectionthereof extending into the region of said handle for selectively haltingoscillating movement of said blade and for locking the latter into apredetermined position intermediate said divergent limits whereby toconstitute a ruddering effect of said blade;

wherein said blade includes a tubular mounting portion and defines apair of radially opposite slots extending transversely relative to themain axis of said mounting portion, and wherein said limit meanscomprises a depressible stop member extending from said angularprojection, said blade being arranged to be rotated relative to saidmounting portion upon depressing said stop member such as to permitdisplacement of said blade through from one direction to an axiallyopposite direction in which position said pin extends into the other oneof said slots; and

wherein said handle defines a plurality of openings therein spacedcircumferentially, equidistant from each other, and

wherein said shaft end comprises a normally protruding depressible pinmember and adapted to be snapped into any of said openings in saidhandle upon insertion of said handle into said shaft end such as to locksaid handle in a desired position relative to said shaft.

9. Impeller for small boats comprising:

a shaft adapted to extend generally horizontally over a boat transom andincluding an angular projection depending substantially vertically intothe water spaced from the boat;

a handle for oscillating said shaft and said angular projection thereof,said shaft and handle including adjustable means for permitting saidhandle to be snapped from one offset position to'a plurality of suchpositions with respect to said shaft;

means adapted to mount said shaft'to the boat for universal pivotalmovement;

at least one generally planar blade pivotally attached to said angularprojection for oscillating movement relative to said angular projectionin response to oscillation of said handle;

limit means on said angular projection and said blade for limiting theoscillating movement of said blade between divergent limits, said limitmeans permitting said blade to snap from one oscillating position toanother relative to said angular projection; and

manually operable control means on said shaft and said projectionthereof extending into the region of said handle for selectively haltingoscillating movement of said blade and for locking the latter into apredetermined position intermediate said divergent limits whereby toconstitute a ruddering effect of said blade; and wherein said blademember includes an elongated tubular sleeve portion, integral with andpivotally mounting said blade member to said suspending arm portion,

ing pin; said locking pin being movable between a locking position inwhich said blade is locked in said cavity relative to said arm portion,and a released position in which said pin is retracted from said cavity.

1. Impeller for small boats, comprising: a shaft adapted to extendgenerally horizontally over a boat transom and including an angularprojection depending substantially vertically into the water and spacedfrom the boat; a handle for oscillating said shaft and said angularprojection thereof; said shaft and handle including adjustable means forpermitting said handle to be snapped from one offset position to aplurality of such positions with respect to said shaft; means adapted tomount said shaft to the boat for universal pivotal movement; at leastone generally planar blade pivotally attached to said angular projectionfor oscillating movement relative to said angular projection in responseto oscillation of said handle; limit means on said angular projectionand said blade for limiting the oscillating movement of said bladebetween divergent limits, said limit means permitting said blade to snapfrom one oscillating position to another relative to said angularprojection; and manually operable control means on said shaft and saidprojection thereof for selectively halting oscillating movement of saidblade and for locking the latter into a predetermined positionintermediate said divergent limits whereby to constitute a rudderingeffect of said blade; wherein said blade constitutes a unitary memberincluding a tubular mounting portion defining a slot extendingtransversely relative to the longitudinal axis of said mounting portion,and wherein said limit means comprises a stop member extending outwardfrom said angular projection into said slot and movable therein betweenopposite ends thereof to limit the rotation of said blade.
 2. Impellerfor small boats, comprising: a shaft adapted to extend generallyhorizontally over a boat transom and including an angular projectiondepending substantially vertically into the water spaced from the boat;a handle for oscillating said shaft and said angular projection thereof;said shaft and handle including adjustable means for permitting saidhandle to be snapped from one offset position to a plurality of suchpositions with respect to said shaft; means adapted to mount said shaftto the boat for universal pivotal movement; at least one generallyplanar blade pivotally attached to said angular projection foroscillating movement relative to said angular projection in response tooscillation of said handle; limit means on said angular projection andsaid blade for limiting the oscillating movement of said blade betweendivergent limits, said limit means permitting said blade to snap fromone oscillating position to another relative to said angular projection;and manually operable control means on said shaft and said projectionthereof for selectively halting oscillating movement of said blade andfor locking the latter into a predetermined position intermediate saiddivergent limits whereby to constitute a ruddering effect of said blade;wherein said blade includes a tubular mounting portion and defines apair of radially opposite slots extending transversely relative to themain axis of said mounting portion; and wherein said limit meanscomprises a depressible stop member extending from said angularprojection, said blade being arranged to be rotated relative to saidmounting portion upon depressing said stop member such as to permitdisplacement of said blade through 180* from one direction to an axiallyopposite direction in which position said pin extends into the other oneof said slots.
 3. Impeller for small boats comprising: a shaft adaptedto extend generally horizontally over a boat transom and including anangular projection depending substantially vertically into the waterspaced from the boat; a handle for oscillating said shaft and saidangular projection thereof; said shaft and handle including adjustablemeans for permitting said handle to be snapped from one offset positionto a plurality of such positions with respect to said shaft; meansadapted to mount said shaft to the boat for universal pivotal movement;at least one generally planar blade pivotally attached to said angularprojection for oscillating movement relative to said angular projectionin response to oscillation of said handle; limit means on said angularprojection and said blade for limiting the oscillating movement of saidblade between divergent limits, said limit means permitting said bladeto snap from one oscillating position to another relative to saidangular projection; and manually operable control means on said shaftand said projection thereof for selectively halting oscillating movementof said blade and for locking the latter into a predetermined positionintermediate said divergent limits whereby to constitute a rudderingeffect of said blade; wherein said shaft includes a tubular extensionincluding said vertical arm portion depending therefrom; and whereinsaid blade comprises a unitary member including an elongated sleeverotatable about said vertical portion and defining a pair of radiallyopposite slots therein extending transversely relative to axis of saidsleeve; and wherein said vertical arm portion comprises a normallyprotruding pin member, depressible relative to said vertical arm portionand adapted to be selectively journaled between the ends of said slotssuch as to limit oscillating movement of said blade relative to said armportion.
 4. Impeller for small boats comprising: a shaft adapted toextend generally horizontally over a boat transom and including anangular projection depending substantially vertically into the waterspaced from the boat; a handle for oscillating said shaft and saidangular projection thereof; said shaft and handle including adjustablemeans for permitting said handle to be snapped from one offset positionto a plurality of such positions with respect to said shaft; meansadapted to mount said sahft to the boat for universal pivotal movement;at least one generally planar blade pivotally attached to said angulArprojection for oscillating movement relative to said angular projectionin response to oscillation of said handle; limit means on said angularprojection and said blade for limiting the oscillating movement of saidblade between divergent limits, said limit means permitting said bladeto snap from one oscillating position to another relative to saidangular projection; and manually operable control means on said shaftand said projection thereof for selectively halting oscillating movementof said blade and for locking the latter into a predetermined positionintermediate said divergent limits whereby to constitute a rudderingeffect of said blade; wherein said shaft includes a tubular extensionincluding a vertical arm portion depending therefrom; and wherein saidblade includes an integral elongated sleeve member rotatable withpredetermined limits about said arm portion and defining a pair ofradially opposed arcuately shaped slots therein extending transverselyrelative to the axis of elongation of said sleeve portion; and whereinsaid vertical arm comprises a normally protruding pin member, manuallydepressible relative to said vertical arm, said blade being arranged tobe rotated relative to said vertical arm upon depressing said pin membersuch as to permit displacement of said blade through 180* from onedirection to an axially opposite direction in which position said pinmember extends into the other one of said slots.
 5. A sculling oarcomprising: a shaft, means for mounting said shaft to overhang the edgeof a watercraft to be propelled, an extension for said shaft includingan angular depending portion and a tubular portion extendingsubstantially vertically, a blade secured about said tubular portion forrotatable movement about a substantially vertical axis, first pin meanswithin said tubular portion engaging stops integral with said blade forlimiting angular movement of said blade, second pin means extendable inand out of said blade and tubular portions of said extension forselectively locking and unlocking said blade for oscillatory movementabout said tubular portion of said extension, and means secured to saidshaft for controlling said second pin means.
 6. The combination inaccordance with claim 5 wherein a pair of extensions are connected tosaid shaft and each having a respective blade secured thereto, said pairof extensions having lateral angular displacement from each other toprovide a pair of laterally displaced blades controlled by said shaft.7. The combination in accordance with claim 5 wherein said extensionsare angularly adjustable.
 8. Impeller for small boats comprising: ashaft adapted to extend generally horizontally over a boat transom andincluding an angular projection depending substantially vertically intothe water spaced from the boat; a handle for oscillating said shaft andsaid angular projection thereof, said shaft and handle includingadjustable means for permitting said handle to be snapped from oneoffset position to a plurality of such positions with respect to saidshaft; means adapted to mount said shaft to the boat for universalpivotal movement; at least one generally planar blade pivotally attachedto said angular projection for oscillating movement relative to saidangular projection in response to oscillation of said handle; limitmeans on said angular projection and said blade for limiting theoscillating movement of said blade between divergent limits, said limitmeans permitting said blade to snap from one oscillating position toanother relative to said angular projection; and manually operablecontrol means on said shaft and said projection thereof extending intothe region of said handle for selectively halting oscillating movementof said blade and for locking the latter into a predetermined positionintermediate said divergent limits whereby to constitute a rudderingeffect of Said blade; wherein said blade includes a tubular mountingportion and defines a pair of radially opposite slots extendingtransversely relative to the main axis of said mounting portion, andwherein said limit means comprises a depressible stop member extendingfrom said angular projection, said blade being arranged to be rotatedrelative to said mounting portion upon depressing said stop member suchas to permit displacement of said blade through 180* from one directionto an axially opposite direction in which position said pin extends intothe other one of said slots; and wherein said handle defines a pluralityof openings therein spaced circumferentially, equidistant from eachother, and wherein said shaft end comprises a normally protrudingdepressible pin member and adapted to be snapped into any of saidopenings in said handle upon insertion of said handle into said shaftend such as to lock said handle in a desired position relative to saidshaft.
 9. Impeller for small boats comprising: a shaft adapted to extendgenerally horizontally over a boat transom and including an angularprojection depending substantially vertically into the water spaced fromthe boat; a handle for oscillating said shaft and said angularprojection thereof, said shaft and handle including adjustable means forpermitting said handle to be snapped from one offset position to aplurality of such positions with respect to said shaft; means adapted tomount said shaft to the boat for universal pivotal movement; at leastone generally planar blade pivotally attached to said angular projectionfor oscillating movement relative to said angular projection in responseto oscillation of said handle; limit means on said angular projectionand said blade for limiting the oscillating movement of said bladebetween divergent limits, said limit means permitting said blade to snapfrom one oscillating position to another relative to said angularprojection; and manually operable control means on said shaft and saidprojection thereof extending into the region of said handle forselectively halting oscillating movement of said blade and for lockingthe latter into a predetermined position intermediate said divergentlimits whereby to constitute a ruddering effect of said blade; andwherein said blade member includes an elongated tubular sleeve portion,integral with and pivotally mounting said blade member to saidsuspending arm portion, said sleeve portion defining a cavity therein,and wherein said manually operable control means comprises a locking pinadapted to be relatively positioned within said cavity, a lever-memberon said shaft, and means interconnecting said locking pin and said levermember for actuation or de-actuation of said locking pin; said lockingpin being movable between a locking position in which said blade islocked in said cavity relative to said arm portion, and a releasedposition in which said pin is retracted from said cavity.